Device for attaching a front loader to a tractor

ABSTRACT

This invention relates to a device for attaching a front loader to a tractor. Said device comprises connection means pivotally connecting bases of a pair of lift arms mounted at opposite sides of the front loader with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, bed plate means mounted at opposite sides of a body of the tractor, elements provided in said connection means, and elements provided in said bed plate means. Said elements provided in said connection means being engageable with said elements provided in said bed plate means whereby the front loader can be firmly attached to the tractor.

[4 1 Apr. 23, 1974 DEVICE FOR ATTACHING A FRONT LOADER TO A TRACTOR Masami Kisaka, Okayama, Japan Sanyo Kiki Kabushiki Kaisha, Itami City, I-Iyogo Pref., Japan Filed: Mar. 31, 1972 Appl. No.: 240,210

[75] Inventor:

[73] Assignee:

[30] Foreign Application Priority Data Apr. 5, 1971 Japan 46-25107 Apr. 5, 1971 Japan 46-25108 Dec. 27, 1971 Japan 46-1962 References Cited UNITED STATES PATENTS 7/1962 Astrom 214/131 A 10/1971 Eidy 214/131 A FOREIGN PATENTS OR APPLICATIONS 40,447 Finland 214/131 A Primary Examiner-Robert G. Sheridan Assistant Examiner-John Mannix gjttorney, Agent, or Firm-Stevens, Davis, Miller &

Mosher [57] ABSTRACT This invention relates to a device for attaching a front loader to a tractor. Said device comprises connection means pivotally connecting bases of a pair of lift arms mounted at opposite sides of the front loader with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, bed plate means mounted at opposite sides of a body of the tractor, elements provided in said connection means, and elements provided in said bed plate means. Said elements provided in said connection means being engageable with said elements provided in said bed plate means whereby the front loader can be firmly attached to the tractor.

2 Claims, 14 Drawing Figures FIG FIG

TM'ENYEB APR 2 3 [PM SHEET 5 HF 5 FIG l2 FIG FIG I4 DEVICE FOR ATTACHING A FRONT LOADER TO A TRACTOR This invention relates to a device for attaching a front loader to a tractor.

An object of this invention is to provide a device for attaching a front loader to a tractor which is simple in construction and low in cost, and which permits ready attachment of the front loader to the tractor and detachment of the same therefrom with high safety.

Another object of the invention is to provide a device for attaching a front loader to a tractor which comprises connection means for connecting bases of a pair of lift arms mounted at opposite sides of the front loader to bases of a pair of actuating cylinders for the front loader, bed plate means each having attached to its inner opposite sides receiving members and mounted at opposite sides of a body of the tractor, tubular shafts connected to the bases of corresponding lift arms and adapted to be received in recesses formed in the receiving members, and pin means adapted to be inserted in openings formed in the bed plate means and aligned with the recesses formed in the receiving members and the tubular shafts engaged in such recesses, so that the front loader can be firmly attached to the tractor body.

Another object of the invention is to provide a device for attaching a front loader to a tractor which comprises connection means for connecting bases of a pair of lift arms mounted at opposite sides of the front loader to bases of a pair of actuating cylinders for the front loader, bed plate means mounted at opposite sides of a body of tractor, two sets of hooks firmly secured to rear surfaces of the connection means, and two sets of horizontal bars firmly secured to the bed plate means, each set of horizontal rods being adapted to be hitched on to one of the two sets of hooks so as to thereby firmly attach the front loader to the tractor body.

Other objects as well as features and advantages of the invention will become evident from the description set forth hereinafter when considered in conjunction with the accompanying drawings, in which:

FIG. 1 is a side view of a front loader attached to a tractor by the attaching device comprising one embodiment of this invention;

FIG. 2 is a side view of the front loader and the tractor of FIG. 1 shown as the former is detached from the latter;

FIG. 3 is a paln view of FIG. 2;

FIG. 4 is a view in explanation of the manner in which tubular shafts on the front loader side impinge on the receiving members on the tractor side when the front leader is about to be attached to the tractor;

FIG. 5 is a view in explanation of the manner in which the front loader is firmly attached to the tractor by means of the first embodiment of this invention;

FIG. 6 is an exploded view of the attaching device according to this invention in explanation of various parts thereof;

FIG. 7 is a side view of a front loader and a tractor incorporating therein a second embodiment of the attaching device according to this invention, the front loader and tractor being shown as they are detached from each other;

FIG. 8 is a view in explanation of the manner in which the connection means on the front loader side impinges on the horizontal rods on the tractor side when the front loader is about to be attached to the tractor;

FIG. 9 is a view in explanation of the manner in which the front loader is firmly attached to the tractor by means of the second embodiment of this invention;

FIG. 10 is a view in explanation of the manner in which a front loader is firmly attached to a tractor by means of a third embodiment of this invention;

FIG. 11 is a view in explanation of the manner in which the hooks on the front loader side impinge on the horizontal rods on the tractor side when the front loader is about to be attached to the tractor;

FIG. 12 is a view in explanation of the manner in which tubular shafts on the front loader side impinge on the receiving members on the tractor side when the front loader is about to be attached to the tractor by means of a fourth embodiment of this invention:

FIG. 13 is a view in explanation of the manner in which the front loader is attached to the tractor by means of the fourth embodiment; and

FIG. 14 is an exploded view of the fourth embodiment of this invention in explanation thereof.

In the drawings, a designates a tractor, and b a front loader. Tractor a comprises a body 1, and a pair of base plates 2 mounted on body 1 at opposite sides thereof, each base plate 2 including a front end portion 3 which is bent obliquely forwardly downwardly.

A pair of bed plate members 4 are each secured to a rear portion of one of the pair of base plates 2. Bed plate members 4 are in the shape of a letter U in crosssection and inclined obliquely rearwardly with their one open side facing forwardly. Each bed plate member 4 is provided with receiving members 5 secured to upper portions of opposite inner sides thereof. Each receiving member 5 is formed in its intermediate front portion with a forwardly facing cutout 6 and in its lower front portion with an inclined front edge 7 which is inclined obliquely rearwardly upwardly and contiguous with an arcuate engaging recess 8 at its upper end. Each bed plate member 4 is formed in opposite sides thereof with openings 9 which each corresponds in position to the center of one of the recesses 8.

Front loader b comprises a pair of lift arms 10 mounted thereon and disposed at opposite sides thereof. Each lift arm 10 is provided with a receiver 1 l secured to its intermediate portion. A bucket 12 is pivotally and detachably attached to front ends of lift arms 10 for collecting gravels. A cylinder 13 adapted to be disposed below the base of each lift arm 10 receives therein a plunger 14 which is pivotally connected by a pin 15 to the receiver 11. Each lift arm 10 is connected at its base to a connection member 17 of the U-shaped cross-section at its upper opposite sides by a tubular shaft 16, opposite ends of such tubular shaft 16 extending outwardly through opposite sides of each connection member 17. Each cylinder 13 is pivotally connected at its base to a lower portion of the corresponding connection member 17 by a pin 18. 19 is a pin and 20 a check pin. Pin 19 is adapted to be inserted in the openings 9 formed in both sides of each bed plate member 4 and in the hollow shaft 16, and check pin 20 is adapted to hold pin 19 in place.

Tractor a further comprises a pressure fluid outlet port 21 to which a hose 22 is connected. Hose 22 is bifurcated at its front end portion, and a connector 23 is mounted on each of the two front ends of hose 22. Connected to eacy cylinder 13 is a hose 24 which has mounted at its front end a connector 25. 26 designates a stand for temporarily supporting front loader b when it is attached to or detached from tractor a. 27 designates a bucket lock member to which is connected a dump lever 29 which in turn is connected through a wire 30 to a lever 29 mounted on one of the connecting member 17.

Operation of the embodiment of this invention constructed as aforementioned will now be described. In attaching front loader b to tractor a, the pair of lift arms of front loader b are first placed at their intermediate portions on stands 26 as shown in FIG. 2 so that the lower end of each connection member 17 is substantially at the same level as the corresponding base plate 2 of tractor a. While each lift arm 10 is in this position, tractor a is moved toward front loader b as shown in FIG. 2 and FIG. 3. This results in the downwardly bent front portion 3 of each base plate 2 of tractor a impinging on the corresponding connection member 17 of front loader b and guiding the same such that connection member 17 moves on the base plate 2 till it is ultimately brought into engagement with the corresponding bed plate member 4.

After the inclined front edges 7 of oppositely disposed receiving members 5 have impinged on the oppositely disposed extensions of tubular shaft 16 as shown in FIG. 4 prior to ultimate engagement of each connection member 17 with the corresponding bed plate member 4, tubular shaft 16 moves upwardly in sliding motion along the inclined front edges 7 of receiving members 5 as tractor a moves forwardly and consequently loader b pivots counter clockwise in FIG. 4 about a position at which bucket 12 is in contact with the ground, so that each connection member 17 provided with tubular shaft 16 moves upwardly.

After each tubular shaft 16 has passed by the upper ends of the corresponding inclined front edges 7 as tractor a moves forwardly, front loader b is caused by its own weight to pivot in a direction opposite to the direction of previous pivotal movement and the oppositely disposed extensions of tubular shaft 16 are brought into engagement with the recesses 8 formed in the corresponding oppositely disposed receiving members 5 as shown in FIG. 5. At the same time, a rear surface of each connection member 17 is brought into engagement with the corresponding bed plate member 4.

When connection member 17 is in this position, pin 19 is inserted in the openings 9 formed in the oppositely disposed sides of each bed plate member 4 and in each tubular shaft 16 and held in place by check pin 20, thereby firmly securing each connection member 17 to the corresponding bed plate member 4. Then, the stands 26 are removed and the connector 25 of each hose 24 is connected to one of the connectors 23 as shown in FIG. 1, thereby completing the operation of attaching front loader b to tractor a.

In detaching front loader b from tractor a, bucket 12 is placed on the ground as shown in FIG. 1 and check pin 20 and pin 19 are removed from the corresponding tubular shaft 16. Thereafter, fluid under pressure is supplied from pressure fluid outlet port 21 to each 'cylinder 13 through the hoses 22 and 24. This causes the plunger 14 of each cylinder 13 to move forwardly and thrust the intermediate portion of the corresponding lift arm 10, so that front loader b pivots counter clockwise in FIG. 1 about a position at which bucket 12 is in contact with the ground and each tubular shaft 16 moves upwardly away from the corresponding recesses 8. Then, each lift arm 10 is supported by the stand 26 as shown in FIG. 2 and each connector 25 is released from the corresponding connector 23 before tractor a is moved rearwardly. Rearward movement of tractor a causes each tubular shaft 16 to move through the corresponding cutouts 6, so that tractor a detaches itself from front loader b.

It is to be understood that the attaching device according to this invention operates in the same manner as described above when any other working tool than bucket 12, such for example as a fork for handling barnyard manure or grass, is mounted at the front ends of lift arms 10 of front loader b.

The attaching device according to this invention is constructed as aforementioned, so that front loader b can be attached to tractor a or detached therefrom by bringing tubular shafts 16 into and out of engagement with recesses 8 and inserting pins 19 into openings 9 and tubular shafts 16 or removing the same therefrom. Thus, the attaching device according to this invention permits front loader b to be attached to tractor a or detached therefrom with great ease. Even a female operator can perform the attaching and detaching operations by driving tractor a to bring tubular shafts 16 into and out of engagement with recesses 8, without requiring as much manual attention has hitherto been required when conventional attaching devices were used.

The attaching device according to this invention is constructed such that each tubular shaft 16 is concentric with the openings 9 of the corresponding bed plate member 4 when each tubular shaft 16 is in engagement with the corresponding recesses 8. This permits pin 19 to be readily inserted in each tubular shaft 16 and openings 9 without requiring a tool for the purpose.

Besides, each connection member 17 of front loader b is brought into and out of engagement with the corresponding bed plate member 4 of tractor a while each lift arm 10 is connected as a unit to the corresponding cylinder 13 by each connection member 17. This-precludes damage to cylinders 13 and eliminates the need to use a supporter for each cylinder 13.

When tractor a is used for performing an operation in which no front loader b is required, cylinders 13 can also be removed from tractor a so that they may not interfere with the operation. This causes less wear on pins and bosses for front loader b and permits reduction of the weight in a tractor because there is a smaller number of attachments than in conventional tractors. Thus, tractor a can be operated readily because the steering wheel can be manipulated smoothly.

In a second embodiment of this invention, a plurality of horizontal rods 31 are mounted in each bed plate member 4. Horizontal rods 31 are disposed in an intermediate portion of each bed plate member 4 with one horizontal rod being disposed above the other horizontal rod and the upper horizontal rod being disposed rearwardly of the lower horizontal rod asshown in FIG. 8. Each bed plate member 4 has a shaft 32 extending through a lower portion of a rear wall of the member 4. A stopper 34 formed at its front end with a downwardly rearwardly inclined surface 33 is mounted at a front end of shaft 32, and aother stopper 35 is secured to a portion of shaft 32 which extends outwardly through the rear wall. A rear end portion of shaft 32 is bent upwardly so that it may serve as an operation lever 36. A spring 37 is mounted on shaft 32 between stopper 34 and the rear wall of bed plate member 4. A plurality of upwardly directed hooks 38 arranged in two rows are secured to a rear surface of each connection member 17.

This embodiment operates as follows: If tractor a is moved forwardly toward front loader b, the forwardly bent portions 3 of base plates 2 mounted at opposite sides of tractor a will impinge on the respective connection members 17 of front loader b and guide the same so that connection members 17 move on base plates 2 till each connection member 17 is received in the corresponding bed plate member 4.

After stopper 34 has struck the connection member 17, the shaft 32 on which stopper 34 is mounted moves rearwardly against the biasing force of spring 37 as tractor a moves forwardly. After horizontal rods 31 have struck the connection member 17 as shown in FIG. 8, horizontal rods 31 move in sliding motion along the rear surfaces of each connection member 17 as tractor 0 moves forwardly and front loader b pivots counter clockwise in the figure about a position at which bucket 12 is in contact with the ground, thereby causing each connection member 17 to move upwardly.

Upward movement of each connection member 17 results in horizontal rods 31 being hitched on to hooks 38 as shown in FIG. 9. At the same time, shaft 32 is moved forwardly by the biasing force of spring 37 so that stopper 34 finds its way between each connection member 17 and the corresponding base plate 2. Thus, each connection member 17 is supported at its lower end by stopper 34 and the hooks 38 secured to the member 17 hold horizontal rods 31, so that each connection member 17 is firmly secured to the corresponding bed plate member 4 and front loader b is attached to tractor a.

In detaching front loader b from tractor a, bucket 12 is placed on the ground as shown in FIG. 1 and then each lever 36 is turned to face downwardly. This causes stopper 34 to rotate together with shaft 32, so that the inclined surface 33 of stopper 34 faces upwardly and each connection member 17rests on upwardly facing inclined surface 33. This results in shaft 32 mounting stopper 34 to be moved rearwardly by the weight of front loader b against the biasing force of spring 37, with each connection member moving in sliding motion along the upwardly facing inclined surface 33 of the corresponding stopper 34. This causes front loader b to pivot clockwise in FIG. 9 about a position at which bucket 12 is in contact with the ground, so that each connection member 17 moves downwardly into engagement with the corresponding base plate 2 and hooks 38 are released from engagement with horizontal rods 31.

A third embodiment uses a plurality of horizontal plates 3l"in place of horizontal rods 31 as shown in FIG. and FIG. 11. The hooks 38 are downwardly directed and stopper 34 is provided in an upper portion of each bed plate member 4.

In this embodiment, a support cylinder 40 formed in its upper and lower portions with vertical grooves 39 is secured to an upper portion of each bed plate member 4. A shaft 41 inserted in a central opening formed in a rear wall of support cylinder 40 has secured to its front end the stopper 34 fitted in support cylinder 40. Shaft 41 also has secured to its rearwardly extending portion a knob 43 which is formed at its inner side with a projection 42 adapted to engage the upper and lower verti cal grooves 39. A spring 44 is mounted on a portion of shaft 41 between the rear wall of support cylinder and stopper 34.

In this embodiment, if knob 43 is pulled and moved rearwardly as shown in FIG. 11 to bring the projection 42 thereof into engagement with a rear surface of support cylinder 40 and then the tractor is moved forwardly as described with reference to the previous embodiments, each connection member 17 of the front loader will move in sliding motion along the corresponding base plate 2 of the tractor till horizontal plates 31' strike the hooks 38 secured to each connection member 17. Thereafter, front loaded b pivots counter clockwise in FIG. 11 about a position at which the bucket connected to its front end is in contact with the ground. Thus hooks 38 move in sliding motion along horizontal plates 31' and each connection member 17 moves upwardly till hooks 38 ride over upper edges of horizontal plates 31' when front loader b is caused to pivot clockwise in FIG. 1 1 by its own weight, so that hooks 38 are hitched on to horizontal plates 31 as shown in FIG. 10.

If knob 43 is turned at this time and released after projection 42 is brought into alignment with the vertical grooves 39 of support cylinder 40, projection 42 will be caused by the biasing force of spring 44 to be engaged in vertical grooves 39 and stopper 34 will move forwardly so as to lock each connection member 17 in position. Thus, front loader b is attached to tractor a.

In detaching front loader b from tractor a, knob 43 is gripped and moved rearwardly against the biasing force of spring 44 as shown in FIG. 11. Then, knob 43 is suitably turned to bring projection 42 into engagement with the rear surface of support cylinder 40 and cause stopper 34 to move rearwardly away from connection member 17. Thereafter, tractor a is moved forwardly so as to cause horizontal plates 31 to move in sliding motion along connection member 17. This moves connection member 17 upwardly so that the hooks 38 secured thereto also move upwardly out of engagement with horizontal plates 31. If tractor a is moved rearwardly at this time after lift arms 10 are placed on the respective stands, tractor a will detach itself from front loader b.

In a fourth embodiment of this invention, each of the lift arms 10 mounted at opposite sides of the front loader is pivotally connected at its base to the base of the corresponding cylinder 13 by one of the connecting members 17 through a pin 46 in an upper portion of the member 17 and a pin 18 in a lower portion thereof as shown in FIG. 12. A tubular shaft 45 similar to thetubular shaft 16 of the first embodiment is mounted in each connection member 17 of the U-shaped cross-section so as to interconnect oppositely disposed sides thereof substantially in central portions thereof. Tubular shaft 45 has opposite end portions which extend outwardly through the .oppositely disposed sides of each connection member 17 of the U-shaped cross-section. 19 is a pin to be inserted in openings 9 formed in each base plate member 4 and in tubular shaft 45, and 20 a check pin for holding pin 19 in position.

In this embodiment, the base plates 2 provided with bent portions 3 for guiding connection members 17 as described with reference to the first embodiment are omitted. Each tubular shaft 45 is guided in its movement as the outwardly extending opposite end portions thereof move in sliding motion along the inclined front edges 7, and a rear surface of each connection member 17 is brought into engagement with the corresponding bed plate member 4 as soon as tubular shaft 45 is brought into engagement with the recesses 8 of receiving members as shown in FIG. 13. Thus, the force with which the front loader moves in clockwise pivotal motion is borne by the upper portion of each connection member 17 in engagement with the corresponding bed plate member 4 and the force with which the front loader moves in anticlockwise pivotal motion is borne by the lower portion thereof, so that any additional mechanism for hearing pivotal movements can be eliminated.

Since openings 9 are formed substantially in central portions of the oppositely disposed sides of each bed plate member 4 so that each tubular shaft 45 may be concentric with the openings 9 of the corresponding bed plate member 4, any trouble which might preclude the engagement of each tubular shaft 45 with the recesses 8 of the corresponding receiving members 5 can readily be eliminated.

What is claimed is:

l. A device for attaching a front loader to a tractor comprising a plurality of tubular shafts each mounted at a base of one of a pair of lift arms mounted at opposite sides of the front loader so that opposite end portions of each said tubular shaft extend outwardly of the base, connection means pivotally connecting the bases of said pair of lift arms with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, bed plate means mounted at opposite sides of a body of the tractor, a plurality of pairs of openings each pair of openings being formed in oppositely disposed sides of each member of said bed plate means, a plurality of pairs of receiving members each pair of receiving members corresponding to each member of said bed plate means so that each pair is disposed adjacent the oppositely disposed sides of the corresponding member of said bed plate means, each of the pair of receiving members being formed with a forwardly facing cutout in its front portion and having a rearwardly upwardly inclined front edge and an arcuate recess disposed rearwardly of said cutout, and a plurality of sets of pins, a pin of one set being adapted to be inserted in each of said plurality of tubular shafts when it is engaged in the arcuate recesses formed in each of said pair of receiving members. I

2. A device for attaching a front loader to a tractor comprising connection means pivotally connecting bases of a pair of lift arms mounted at opposite sides of the front loader with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, a plurality of tubular shafts each mounted in substantially central portions of oppositely disposed sides of each member of said connection means so that opposite end portions of each said tubular shaft extend outwardly of said oppositely disposed sides, bed plate means mounted at opposite sides of a body of the tractor, a plurality of pairs of openings each pair of openings being formed in oppositely disposed sides of each member of said bed plate means, a plurality of pairs of receiving members each pair of receiving members corresponding to each member of said bed plate means so that each pair is disposed adjacent the'oppositely disposed sides of the corresponding member of said bed plate means, each of the pair of receiving members being formed with a forwardly facing cutout in its front portion and having a rearwardly upwardly inclined front edge and an arcuate recess disposed rearwardly of said cutout, and a plurality of sets of pins, a pin of one set being adapted to be inserted in each of said plurality of tubular shafts when it is engaged in the arcuate recess formed in each of said pair of receiving members. 

1. A device for attaching a front loader to a tractor comprising a plurality of tubular shafts each mounted at a base of one of a pair of lift arms mounted at opposite sides of the front loader so that opposite end portions of each said tubular shaft extend outwardly of the base, connection means pivotally connecting the bases of said pair of lift arms with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, bed plate means mounted at opposite sides of a body of the tractor, a plurality of pairs of openings each pair of openings being formed in oppositely disposed sides of each member of said bed plate means, a plurality of paiRs of receiving members each pair of receiving members corresponding to each member of said bed plate means so that each pair is disposed adjacent the oppositely disposed sides of the corresponding member of said bed plate means, each of the pair of receiving members being formed with a forwardly facing cutout in its front portion and having a rearwardly upwardly inclined front edge and an arcuate recess disposed rearwardly of said cutout, and a plurality of sets of pins, a pin of one set being adapted to be inserted in each of said plurality of tubular shafts when it is engaged in the arcuate recesses formed in each of said pair of receiving members.
 2. A device for attaching a front loader to a tractor comprising connection means pivotally connecting bases of a pair of lift arms mounted at opposite sides of the front loader with bases of a pair of cylinders each having a plunger pivotally supported at an intermediate portion of one of said pair of lift arms, a plurality of tubular shafts each mounted in substantially central portions of oppositely disposed sides of each member of said connection means so that opposite end portions of each said tubular shaft extend outwardly of said oppositely disposed sides, bed plate means mounted at opposite sides of a body of the tractor, a plurality of pairs of openings each pair of openings being formed in oppositely disposed sides of each member of said bed plate means, a plurality of pairs of receiving members each pair of receiving members corresponding to each member of said bed plate means so that each pair is disposed adjacent the oppositely disposed sides of the corresponding member of said bed plate means, each of the pair of receiving members being formed with a forwardly facing cutout in its front portion and having a rearwardly upwardly inclined front edge and an arcuate recess disposed rearwardly of said cutout, and a plurality of sets of pins, a pin of one set being adapted to be inserted in each of said plurality of tubular shafts when it is engaged in the arcuate recess formed in each of said pair of receiving members. 